Joe Biden talks on a cellphone during day one of the Democratic National Convention.

Photo by Win McNamee/Getty Images

Joe Biden says what Joe Biden wants. He shoots from the hip; calls it like he sees it. Joe Biden can own a room. He can also make one squirm. Joe Biden drops the F-bomb from time to time. That’s just how honey badgers are. But, sometimes a politician’s best weapon is also his worst enemy. Like that time at a campaign rally when Biden saluted Missouri state senator Chuck Graham by asking him to stand up and be acknowledged, before realizing Graham was in a wheelchair.

On Tuesday, Biden was at it again. After Boston’s mayoral election results rolled in, Biden got on the horn to congratulate Marty Walsh, the newly elected mayor of the city. “You son of a gun, Marty!” Biden gushed. “You did it!” There was just one problem: he was speaking to the wrong Marty Walsh.

Biden had called the cellphone of Marty Walsh, a former aide to US Senator Edward M. Kennedy who is now the president of Gateway Public Solutions, a government relations firm in Boston.

At the time, this Marty Walsh said, he was sitting on the couch with his wife at their home in Natick, watching the election results on television. Meanwhile, the other Marty Walsh, the one who had just been elected mayor of Boston, was at the Park Plaza Hotel, celebrating his victory.

The less-famous Marty Walsh said he thanked Biden for his kind words, but told him that he reached the wrong Marty. He offered to help the vice president track down the right one, the one who had just been elected mayor.

In fairness to Biden, the non-mayor Marty Walsh told Boston.com he also received congratulatory calls from the mayor of Minneapolis, the vice chairman of the Democratic National Committee, and Rep. Debbie Wasserman Schultz.